The Smurfs made their alleged assault on December 16, 2012, in Pascoe Vale, Victoria, Australia. Australians pronounce Australia as "Ozstralia," and thus so "Oz" is a shortened version of referring to the country, especially by Aussies (Australians) and Kiwis (New Zealanders.

Pascoe Vale was named after the John Pascoe Fawkner Estate, which was originally a holding of 709 acres (2.87 km2). The estate, established in 1839, was bounded by the Moonee Ponds Creek to the west, Gaffney Street to the south, Northumberland Road to the east and Rhodes Parade to the north. John Pascoe Fawkner built a timber house overlooking the creek, in the Marie Street area of Oak Park.John Pascoe Fawkner (20 October 1792 – 4 September 1869) was an early pioneer, businessman and politician of Melbourne, Victoria, Australia. In 1835 he financed a party of free settlers from Van Diemen's Land (now called Tasmania), to sail to the mainland in his ship, Enterprize. Fawkner's party sailed to Port Phillip and up the Yarra River to found a settlement which became the city of Melbourne. Sources: 1, 2 & 3.

The Leprechauns made their appearances in Belltown, Washington State on June 16, 2012, and earlier in March 2006 in Crichton, near Mobile, Alabama.

The Crichton Leprechaun has taken on legendary status, with over 22 million YouTube views of the report. One on-site reporter named Scott Walker remembers that

...the report didn't start out to be about a leprechaun. The TV crew was dispatched to find out why crowds were gathering in the Crichton community. Pronounced Crigh-ton, the area near Toulminville is divided by Spring Hill Avenue into North Crichton and South Crichton, bounded generally by Mobile Street, Dauphin Street and Interstate 65.

It was when the TV crew arrived to find out why people were all gathering that 'things sort of snowballed,' Walker said. 'People were looking up at a tree and saying there was a Leprechaun in it,' he wrote. Source.

Now comes the report from Australia of the Smurfs. Most accounts track back to this version of what occurred, which I summarize here:

A Pascoe Vale, Australia man, 37, bought a packet of cigarettes from a convenience store at the intersection of West and Pascoe streets at about 1:00 am on December 16, 2012. After he left the store an apparent human dressed as a Papa Smurf approached him and asked for a cigarette. The man offered him a smoke but the Smurf insisted it be lit before he handed it over. The man refused and noticed the thing dressed as a Smurf was with three other entities, who were also dressed as Smurfs. The Pascoe Vale man was then smashed and bashed but the police initial reports said they were unclear if the alleged offenders were the "group in fancy dress," as the Australian media called them.

"We are trying to piece it all together to determine the exact circumstances surrounding the assault," the police spokeswoman said. "Because the men dressed as Smurfs spoke to the man before the assault we are interested in talking to them to find out what happened."

The "group in fancy dress" (the Smurfs) apparently tried to jump start a white VS Commodore and had asked for assistance from a woman at a nearby car park before they met the Pascoe Vale man. Source.